In view of the above, it is an object of the invention to form a fishing rod having a delicate flexible characteristic into an intra-line fishing rod which can reduce the insertion resistance of a fishline while maintaining the delicate flexible characteristic thereof.
In attaining the above object, according to the invention, there is provided an intra-line fishing rod using synthetic resin as a matrix and reinforced with reinforcing fibers, in which a rod top portion of the fishing rod is formed substantially in a straight shape with the inside diameter thereof having an inclination of {fraction (3/1000)} or less, reinforcing fibers respectively having different moduli of elasticity are sequentially disposed in the rod top portion in such a manner that the reinforcing fibers extend substantially in the axial direction of the rod top portion, and the elastic moduli increase sequentially in a geometric series manner from the front portion of the rod top portion toward the rear portion thereof.
In the fishing rod, since the inside diameter of the rod top portion is formed substantially straight, the inside diameter of the front portion of the rod top portion can be set large and thus there can be provided a hollow portion through which a fishline can pass freely, thereby being able to provide a fishline insertable structure which can reduce the resistance of the fishline. However, in this structure, as it is, the flexural rigidity of the front portion of the rod top portion is high and is thus difficult to flex. Therefore, by selecting the reinforcing fibers in such a manner that the elastic moduli of the substantially axially extending reinforcing fibers, which contribute to the flexural rigidity, increase sequentially in a geometric series manner from the front portion to the rear portion (that is, the front portion is easy to flex), even if the front portion of the rod top portion is relatively large in diameter, similarly when the front portion of the rod top portion is tapered, the front portion of the rod top portion can be flexed easily and delicately.
Here, the term xe2x80x9csequencexe2x80x9d used in this specification relates to reinforcing fibers which are used as main reinforcing fibers except for reinforcing fibers such as auxiliary prepregs used for partial reinforcement in the guide fixation and the like.
Also, according to the invention, there is provided an intra-line fishing rod in which a layer of reinforcing fibers extending substantially in the circumferential direction of the rod top portion is provided as an inner layer, an outer layer or an intermediate layer of the reinforcing fibers extending substantially in the axial direction of the rod top portion.
In the structure of the fishing rod, when two or more kinds of the above-mentioned substantially axially extending reinforcing fibers are sequentially disposed, it is true that the connecting portions thereof are weak, but, if there is provided a layer of reinforcing fibers extending substantially in the peripheral direction of the rod top portion, then the connecting portions can be reinforced without interfering the delicate flexure thereof and can be prevented against crushing rupture.
Further, according to the invention, there is provided an intra-line fishing rod including a rod top portion which has a matrix formed of synthetic resin and is reinforced not only with reinforcing fibers extending substantially in the axial direction of the top rod portion within the range of angles of xc2x130xc2x0 with respect to the axial direction of the rod top portion but also reinforcing fibers extending substantially in the peripheral direction of the rod top portion within the range of angles of xc2x145xc2x0 with respect to the circumferential direction of the rod top portion, in which the inside diameter of the rod top portion is formed in a substantially straight shape or in a gently tapered shape, and the ratio of the reinforcing fibers extending in said substantially peripheral direction in the front portion of the rod top portion is 50% or greater while the ratio of the reinforcing fibers in the rear portion of the rod top portion is smaller.
According to the fishing rod, since the inside diameter of the rod top portion is formed substantially straight or in a gentle taper, the inside diameter of the front portion of the rod top portion can be set large and thus there can be provided a hollow portion through which a fishline can pass freely, thereby being able to provide a fishline insertable structure which can reduce the resistance of the fishline. However, in this structure, as it is, the flexural rigidity of the front portion of the rod top portion is high and is thus difficult to flex. In view of this, in the front portion of the rod top portion, the ratio of the reinforcing fibers extending substantially in the peripheral direction of the rod top portion is set for 50% or more while the ratio of the reinforcing fibers extending in the longitudinal direction is set smaller; and, on the other hand, in the rear portion of the rod top portion, the ratio of the reinforcing fibers extending substantially in the peripheral direction is set small while the ratio of the longitudinally extending reinforcing fibers is set large. Since the characteristic of flexure depends on the longitudinally extending reinforcing fibers, the smaller the ratio of the longitudinally extending reinforcing fibers is, the lower the rigidity is; that is, there can be provided a fishing rod which is easy to flex. Therefore, even if the rod top portion is large in diameter, the flexing property thereof can be made delicate similarly to a tapered rod top portion. In this specification, the term xe2x80x9cgentle taperxe2x80x9d is used to express a taper in the range of {fraction (3/1000)} to {fraction (6/1000)}.
According to the invention, there is provided an intra-line fishing rod including a matrix formed of synthetic resin, reinforced with reinforcing fibers, and including a main body layer of a rod top portion having reinforcing fibers extending substantially in the axial direction of the rod top portion, in which the amount of the reinforcing fibers extending substantially in the axial direction in the front portion of the rod top portion is set smaller while the amount of the reinforcing fibers in the rear portion of the rod top portion is set greater, the ratio of the synthetic resin in the front portion of the rod top portion is set greater while the ratio of the synthetic resin in the rear portion of the rod top portion is set smaller, and the inside diameter of the rod top portion is formed in a substantially straight shape or in a gently tapered shape.
Since the inside diameter of the rod top portion is formed substantially straight or in a gentle taper, the inside diameter of the front portion of the rod top portion can be set large and thus there can be provided a hollow portion through which a fishline can pass freely, thereby being able to provide a fishline insertable structure which can reduce the insertion resistance of the fishline. However, in this structure, as it is, the flexural rigidity of the front portion of the rod top portion is high and is thus difficult to flex. In view of this, in the front portion of the rod top portion, the reinforcing fibers extending substantially in the axial direction thereof are small in quantity, whereas the reinforcing fibers extending substantially in the axial direction are large in quantity. Also, in order to reinforce the rod tube against crushing rupture, a larger ratio of synthetic resin is used in the front portion of the rod top portion while a smaller ratio of synthetic resin is used in the rear portion of the rod top portion to thereby keep the strength of the rod tube. Since the flexural property depends on the reinforcing fibers extending substantially in the axial direction, according to the present structure, there can be provided a fishing rod which is easier to flex in the front portion of the rod top portion, and the flexural property of the present top rod portion can be made as delicate as a tapered rod top portion.
According to the invention, there is provided an intra-line fishing rod including a rod top portion, the rod top portion being structured such that synthetic resin is used as a matrix, reinforcing fibers are disposed such that they extend in an inclined direction with the angles of inclination in the range of 5 degrees to 25 degrees with respect to the axial direction of the rod top portion, the reinforcing fibers crossing each other from both right and left directions substantially symmetrically with respect to the axial direction, and the crossing reinforcing fibers occupy almost all of the reinforcing fibers that are used in the rod top portion.
Since the crossing reinforcing fibers are disposed substantially symmetrically, the rod top portion can be prevented from being twisted. And, the axially extending components of the obliquely extending reinforcing fibers contribute to the axial direction, the flexural rigidity in flexing can be controlled down to a low level to thereby be able to provide a large inside diameter accordingly. Also, since the reinforcing fibers extend obliquely, they also have a component which contributes to the peripheral direction, thereby being able to prevent the rod top portion against crushing rupture. The peripheral direction contributing components of the reinforcing fibers cooperate with the axial direction contributing components thereof can prevent the rod top portion from being plastically deformed when it is flexed greatly.
According to the invention, there is provided an intra-line fishing rod including a rod top portion, the rod top portion being structured such that synthetic resin is used as a matrix, reinforcing fibers are disposed such that they extend in an inclined direction with the angles of inclination of 5 degrees or greater with respect to the axial direction of the rod top portion and also such that they cross each other from both right and left directions substantially symmetrically with respect to said axial direction, and a smaller amount of reinforcing fibers than the amount of the crossing reinforcing fibers are disposed so as to extend substantially in the axial direction, or reinforcing fibers having a lower elastic modulus than the crossing reinforcing fibers are disposed so as to extend substantially in said axial direction.
According to the fishing rod, the symmetric arrangement of the reinforcing fibers disposed crossingly from both directions prevents the rod top portion from being twisted. Since a smaller quantity of reinforcing fibers or reinforcing fibers having a low elastic modulus are used in the axial direction, the flexural rigidity of the top rod portion in flexing can be controlled down to a low level, which makes it possible to increase the inside diameter of the rod top portion accordingly. The existence of the reinforcing fibers crossing obliquely provides a component which contributes to the peripheral direction of the rod top portion, thereby being able to protect the rod top portion against crushing rupture. This cooperates with the existence of the axially extending reinforcing fibers to prevent the rod top portion from being deformed plastically when it is flexed greatly.
Also, according to the invention, there is provided an intra-line fishing rod including a rod top portion, the rod top portion being structured such that synthetic resin is used as a matrix, and reinforcing fibers are disposed so as to extend substantially in the axial direction of the rod top portion in such a manner that those of the reinforcing fibers having a large rupture elongation are disposed on the outer side of said rod top portion while those of the reinforcing fibers having a small rupture elongation are disposed on the inner side thereof.
According to the structure, it is generally known that a reinforcing fiber having a large breakage elongation is highly elastic while a reinforcing fiber having a small breakage elongation is low in elasticity. In view of this, in the present structure, since reinforcing fibers having a large breakage elongation are disposed on the outer side of the rod top portion while reinforcing fibers having a small breakage elongation are disposed on the inner side thereof, the rod top portion is easy to flex (the inside diameter of the rod top portion can be increased) but is difficult to be plastically deformed.
Further, according to the invention, there is provided an intra-line fishing rod including a rod top portion, the rod top portion structured such that, there is provided a spirally shaped member through which a fishline can be inserted, and a cylindrical member is provided so as to cover the outer side of the spirally shaped member, the cylindrical member being formed of material having a lower elastic modulus than the spirally shaped member. The term xe2x80x9cspirally shaped memberxe2x80x9d used here includes a member which is produced by connecting a plurality of ring members with a longitudinally extending member.
Since the spirally shaped member is very small in flexural rigidity and the cylindrical member covering the spirally shaped member is also formed of a material having a low elastic modulus, the rod top portion can be enhanced in flexibility and thus the inside diameter of the rod top portion can be increased accordingly. Also, the presence of the spirally shaped member provides a high strength against crushing rupture.